• Title/Summary/Keyword: Surface activation

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Cell-type Specific Activation of MAPKs in the Progression of Gastric Ulcer in Rats (위궤양의 진행에 있어 MAPKs의 세포특이적 활성)

  • Yu, Ri;Kwon, Young Sam;Oh, Tae-Ho;Kim, Tae-Hwan;Park, Sang-Joon
    • Journal of Veterinary Clinics
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    • v.30 no.5
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    • pp.339-345
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    • 2013
  • Mitogen-activated protein kinases (MAPKs) are a family of central signaling molecules that respond to numerous stimuli and are known to participate in processes of cell survival and death. However, it is not clear on data for cell-type specific activation of MAPKs in the progression of gastric ulcer. In the present study, we assessed how MAPKs localized at various cell types during the progression of gastric ulcer induced by ibuprofen. Gastric ulcer was induced by the repeated treatment of 200 mg/kg ibuprofen with 8 hrs interval in a day. Animals were sacrificed at 24 hrs, 48 hrs, and 72 hrs after oral treatment of ibuprofen and gastric tissues were subjected to immunohistochemical and immunoblotting evaluation. Immunoreactivity of phospho-extracellular signal-regulated kinase (p-ERK) was mainly expressed at the proliferating zone of gastric mucosa in control rats. But, these signals for p-ERK were highly shifted from cells of proliferating zone to parietal cells of the basal regions 24 hrs after treatment of ibuprofen. p-ERK signal was strongly expressed in epithelial cells adjacent to ulcer margin and new capillary and infiltrated inflammatory cells within granulation tissue of the ulcer base above 48 hrs after treatment of ibuprofen. While, phospho-c-Jun $NH_2$ terminal kinase (p-JNK) was mainly localized to the nuclei of the surface epithelial cells and the glandular epithelial cells in early gastric injury. Also, p-JNK was often observed as a scattered pattern in different regions of gastric mucosa with early gastric injury. Gradually, signal of p-JNK was strongly stained in infiltrated inflammatory cells and fibroblasts within severe ulcer base. Phospho-p38 (p-p38) MAPK was observed as scattered pattern within connective tissues of gastric mucosa. Especially, p-p38 MAPK showed strong signal in infiltrated macrophages within ulcer base. These results show that each MAPK has a specific role in various cell types during the progression of gastric ulcer.

Activation Analysis of Dual-purpose Metal Cask After the End of Design Lifetime for Decommission (설계수명 이후 해체를 위한 금속 겸용용기의 방사화 특성 평가)

  • Kim, Tae-Man;Ku, Ji-Young;Dho, Ho-Seog;Cho, Chun-Hyung;Ko, Jae-Hun
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.14 no.4
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    • pp.343-356
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    • 2016
  • The Korea Radioactive Waste Agency (KORAD) has developed a dual-purpose metal cask for the dry storage of spent nuclear fuel that has been generated by domestic light-water reactors. The metal cask was designed in compliance with international and domestic technology standards, and safety was the most important consideration in developing the design. It was designed to maintain its integrity for 50 years in terms of major safety factors. The metal cask ensures the minimization of waste generated by maintenance activities during the storage period as well as the safe management of the waste. An activation evaluation of the main body, which includes internal and external components of metal casks whose design lifetime has expired, provides quantitative data on their radioactive inventory. The radioactive inventory of the main body and the components of the metal cask were calculated by applying the MCNP5 ORIGEN-2 evaluation system and by considering each component's chemical composition, neutron flux distribution, and reaction rate, as well as the duration of neutron irradiation during the storage period. The evaluation results revealed that 10 years after the end of the cask's design life, $^{60}Co$ had greater radioactivity than other nuclides among the metal materials. In the case of the neutron shield, nuclides that emit high-energy gamma rays such as $^{28}Al$ and $^{24}Na$ had greater radioactivity immediately after the design lifetime. However, their radioactivity level became negligible after six months due to their short half-life. The surface exposure dose rates of the canister and the main body of the metal cask from which the spent nuclear fuel had been removed with expiration of the design lifetime were determined to be at very low levels, and the radiation exposure doses to which radiation workers were subjected during the decommissioning process appeared to be at insignificant levels. The evaluations of this study strongly suggest that the nuclide inventory of a spent nuclear fuel metal cask can be utilized as basic data when decommissioning of a metal cask is planned, for example, for the development of a decommissioning plan, the determination of a decommissioning method, the estimation of radiation exposure to workers engaged in decommissioning operations, the management/reuse of radioactive wastes, etc.

Understanding the Electrical Property of Si-doped β-Ga2O3 via Thermal Annealing Process (열처리 공정을 이용한 Si-doped β-Ga2O3 박막의 전기적 특성의 이해)

  • Lee, Gyeongryul;Park, Ryubin;Chung, Roy Byung Kyu
    • Journal of the Microelectronics and Packaging Society
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    • v.27 no.4
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    • pp.19-24
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    • 2020
  • In this work, the electrical property of Si-doped β-Ga2O3 was investigated via a post-growth annealing process. The Ga2O3 samples were annealed under air (O-rich) or N2 (O-deficient) ambient at 800~1,200℃ for 30 mins. There was no correlation between the crystalline quality and the electrical conductivity of the films within the experimental conditions explored in this work. However, it was observed the air ambient led to severe degradation of the film's electrical conductivity while N2-annealed samples exhibited improvement in both the carrier concentration and Hall mobility measured at room temperature. Interestingly, the x-ray photoemission spectroscopy (XPS) revealed that both annealing conditions resulted in higher concentration of oxygen vacancy (VO). Although it was a slight increase for the air-annealed sample, high resistivity of the film strongly suggests that VO cannot be a shallow donor in β-Ga2O3. Therefore, the enhancement of the electrical conductivity of N2-annealed samples must be originated from something other than VO. One possibility is the activation of Si. The XPS analysis of N2-annealed samples showed increasing relative peak area of Si 2p associated with SiOx with increasing annealing temperature from 800 to 1,200℃. However, it was unclear whether or not this SiOx was responsible for the improvement as the electrical conductivity quickly degraded above 1,000℃ even under N2 ambient. Furthermore, XPS suggested the concentration of Si actually increased near the surface as opposed to the shift of the binding energy of Si from its initial chemical state to SiOx state. This study illustrates the electrical changes induced by a post-growth thermal annealing process can be utilized to probe the chemical and electrical states of vacancies and dopants for better understanding of the electrical property of Si-doped β-Ga2O3.

Effects of the Pelvic Compression Belt on Trunk Muscles Activities During Sit-to-Stand, and Stand-to-Sit Tasks (골반압박벨트가 앉아서 일어서기와 일어서서 앉기 동작 시 체간근육 근활성도에 미치는 영향)

  • Jang, Hyun-Jeong;Kim, Suhn-Yeop;Park, Hyun-Ju
    • Physical Therapy Korea
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    • v.20 no.1
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    • pp.1-9
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    • 2013
  • The purpose of this study was to determine the effect of the pelvic compression belt (PCB) on the electromyography (EMG) activities of trunk muscles during sit-to-stand (SitTS), and stand-to-sit (StandTS) tasks. Twenty healthy subjects (7 men and 13 women) were recruited for this study. The subjects performed SitTS, and StandTS tasks, with and without a PCB. Surface EMG was used to record activity of the internal oblique (IO), external oblique (EO), rectus abdominis (RA), erector spinae (ES), and multifidus (MF) of the dominant limb. EMG activity significantly decreased in the RA (without the PCB, $8.34{\pm}6.04$ %maximal voluntary isometric contraction [%MVIC]; with the PCB, $7.64{\pm}5.11$ %MVIC), EO (without the PCB, $14.83{\pm}11.82$ %MVIC; with the PCB, $11.98{\pm}7.60$ %MVIC), MF (without the PCB, $21.74{\pm}7.76$ %MVIC; with the PCB, $18.50{\pm}8.04$ %MVIC), and ES (without the PCB, $18.39{\pm}7.16$ %MVIC; with the PCB, $16.63{\pm}6.31$ %MVIC) during the SitTS task and in the IO (without the PCB, $20.58{\pm}15.60$ %MVIC; with the PCB, $17.27{\pm}12.32$ %MVIlC), RA (without the PCB, $8.04{\pm}5.68$ %MVIC; with the PCB, $7.40{\pm}4.71$ %MVIC), EO (without the PCB, $13.29{\pm}8.80$ %MVIC; with the PCB, $11.24{\pm}6.14$ %MVIC), MF (without the PCB, $18.59{\pm}7.64$ %MVIC; with the PCB, $15.86{\pm}6.48$ %MVIC), and ES (without the PCB, $17.14{\pm}6.44$ %MVIC; with the PCB, $15.46{\pm}5.62$ %MVIC) during the StandTS task when a PCB was used (p<.05). In men the EMG activity of the MF significantly decreased during the SitTS task when a PCB was used (p<.05): in women, the EMG activity of the RA, EO, MF, and ES during the SitTS task and that of the EO, MF, and ES during the SitTS task significantly decreased when a PCB was used (p<.05). In addition, the rates of change in the EMG activity of each muscle differed significantly during the SitTS and StandTS tasks before and after the use of the PCB. However, the EMG activity did not significantly differ between the male and female subjects. These findings suggest that the PCB may contribute to the modification of activation patterns of the trunk muscles during SitTS, and StandTS tasks.

Development of Light-weight Fire Protection Materials Using Fly Ash and Light-weight Aggregate (플라이애시 및 경량골재를 활용한 경량 내화성 마감재료 개발)

  • Song, Hun;Chu, Yong-Sik;Lee, Jong-Kyu;Lee, Sea-Hyun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.6 no.4
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    • pp.95-102
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    • 2012
  • The serious issue of tall building is to ensure the fire resistance of high strength concrete. Therefore, Solving methods are required to control the explosive spalling. The fire resistant finishing method is installed by applying a fire resistant material as a light-weight material to structural steel and concrete surface. This method can reduce the temperature increase of the reinforcement embedded in structural steel and concrete at high temperature due to the installation thickness control. This study is interested in identifying the effectiveness of light-weight fire protection material compounds including the inorganic admixture such as fly ash, meta-kaolin and light-weight aggregate as the fire resistant finishing materials through the analysis of fire resistance and components properties at high temperature. Also, this paper is concerned with change in microstructure and dehydration of the light-weight fire protection materials at high temperatures. The testing methods of fire protection materials in high temperature properties are make use of SEM and XRD. The study results show that the light-weight fire resistant finishing material composed of fly ash, meta-kaolin and light-weight aggregate has the thermal stability of the slight decrease of compressive strength at high temperature. These thermal stability is caused by the ceramic binding capacity induced by alkali activation reaction by the reason of the thermal analysis result not showing the decomposition of calcium hydrate. Developed light-weight fire protection materials showed good stability in high Temperatures. Thus, the results indicate that it is possible to fireproof panels, fire protection of materials.

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Effects of Sodium Butyrate, a Histone Deacetylase Inhibitor, on TRAIL-mediated Apoptosis in Human Bladder Cancer Cells (인체 방광암세포에서 histone deacetylase 억제제인 sodium butyrate이 TRAIL에 의한 apoptosis 유도에 미치는 영향)

  • Han, Min-Ho;Choi, Yung Hyun
    • Journal of Life Science
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    • v.26 no.4
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    • pp.431-438
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    • 2016
  • The tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is considered a promising anticancer agent due to its unique ability to induce cancer cell death having only negligible effects on normal cells. However, many cancer cells tend to be resistant to TRAIL. In this study, we investigated the effects and molecular mechanisms of sodium butyrate (SB), a histone deacetylase inhibitor, in sensitizing TRAIL-induced apoptosis in 5637 human bladder cancer cells. Our results indicated that co-treatment with SB and TRAIL significantly increased the apoptosis induction, compared with treatment with either agent alone. Co-treatment with SB and TRAIL effectively increased the cell-surface expression of death receptor (DR) 5, but not DR4, which was associated with the inhibition of cellular Fas-associated death domain (FADD)-like interleukin-1β-converting enzyme (FLICE) inhibitory protein (c-FLIP). Furthermore, the activation of caspases (caspase-3, -8 and -9) and degradation of poly(ADP-ribose) were markedly increased in 5637 cells co-treated with SB and TRAIL; however, the synergistic effect was perfectly attenuated by caspase inhibitors. We also found that combined treatment with SB and TRAIL effectively induced the expression of pro-apoptotic Bax, cytosolic cytochrome c and cleave Bid to truncated Bid (tBid), along with down-regulation of anti-apoptotic Bcl-xL expression. These results collectively suggest that a combined regimen of SB plus TRAIL may offer an effective therapeutic strategy for safely and selectively treating TRAIL-resistant bladder cancer cells.

Experimental Study on Long-term Characteristics of Sprayable Waterproofing Membrane (차수용 박층 멤브레인의 장기 성능 변화에 관한 실험 연구)

  • Choi, Soon-Wook;Kim, Jintae;Choi, Myung-Sik;Chang, Soo-Ho;Kang, Tae-Ho;Lee, Chulho
    • Journal of the Korean Geosynthetics Society
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    • v.18 no.4
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    • pp.15-23
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    • 2019
  • The sprayable waterproofing membrane is a recently introduced material in the civil engineering field, and is a material that sprays and attaches a single phase or two phase powder or liquid material to a surface to be covered using a pump and nozzle. Although the material properties are gradually reported through researches, there is a lack of studies on long-term performance compared to concrete materials used with the membranes. In this study, the long-term performance of materials was estimated using the Arrhenius equation. The temperature conditions used in this study were 65℃, 80℃ and 95℃, and the temperature was maintained with the membrane attached to the concrete block for long-term behavior. Then the membranes were tested for tensile strength and adhesion strength in the order of 30, 90, 150, 200, and 300 days. The long-term performance of the material was determined from a long-term perspective by estimating the activation energy by the Arrhenius equation. Consequently, the time to reach 50% of the performance standard could be estimated by long-term test.

Development of Porous Media for Sewage Treatment by Pyrolysis Process of Food Wastes with Loess (음식물 쓰레기 및 황토 혼합물의 열분해를 통한 수질정화용 다공성 담체 개발)

  • Kim, Sang-Bum;Lee, Myong-Hwa;Kim, Yong-Jin;Park, Chul-Hwan;Lee, Jong-Rae;Kim, Gyung-Soo
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.3
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    • pp.289-296
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    • 2007
  • Porous media for sewage treatment were developed through a pyrolysis process of food wastes with loess in the study. This work was carried out in two consecutive stages; in the first stage, new porous media were prepared through a high temperature pyrolysis process, and then the resultant media were applied to a simple lab-scale sewage treatment process in the second stage. To determine the optimum operating conditions of pyrolysis and mixing ratio of materials, physical properties such as specific surface area, porosity and compressive strength of final products were analyzed. The removal efficiencies of TOC and COD were measured to evaluate the effectiveness of resultant porous media. As a result of the experiment, we found that the best mixing ratio of food wastes to loess was 1 : 1 at $1,100^{\circ}C$. Average porosity of the developed media was 37.0%, in which pore size ranged from 1 to $20{\mu}m$, showing quite vigorous microbial activation. After immersing the media into a reactor for sewage treatment for eight days, removal efficiencies of TOC and COD were 87.3% and 85.0%, respectively.

Immunological Synergistic Effects of Combined Treatment with Herbal Preparation (HemoHIM) and Red Ginseng Extracts (마우스세포를 이용한 홍삼추출물과 생약복합추출물의 병용 처리에 따른 면역활성 효과)

  • Byun, Myung-Woo;Byun, Eui-Hong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.2
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    • pp.182-190
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    • 2015
  • This present study demonstrates the immunological synergistic effects of herbal preparation (HemoHIM) and red ginseng powder granule in various immune cell models (bone marrow-derived macrophages, dendritic cells, and mouse splenocytes) from mice. Both herbal preparation and red ginseng extracts were treated to bone-marrow derived macrophages, dendritic cells, and mouse splenocytes, and there was no cytotoxicity at a dose below $200{\mu}g/mL$. Cell proliferation and cytokine [tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-6, and IL-12] production tested in bone marrow-derived macrophages and dendritic cells significantly increased upon combined treatment. Cell surface marker (CD 80/86, MHC class I/II)-mediated immune cell activation was highly elevated by combined treatment. For cytokine production in splenocytes, combined treatment significantly increased production of Th 1 type cytokines [IL-2 and interferon (IFN)-${\gamma}$] but not Th 2 type cytokines (IL-4 and IL-10). Therefore, combined treatment with HemoHIM and red ginseng extracts is an effective method to establish powerful immunological synergy in immune cells.

Influence of Textural Structure by Heat-treatment on Electrochemical Properties of Pitch-based Activated Carbon Fiber (열처리 온도에 의한 피치계 활성탄소섬유의 기공구조 변화가 전기화학적 특성에 미치는 영향)

  • Kim, Kyung Hoon;Park, Mi-Seon;Jung, Min-Jung;Lee, Young-Seak
    • Applied Chemistry for Engineering
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    • v.26 no.5
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    • pp.598-603
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    • 2015
  • In this study, electrochemical properties of pitch-based activated carbon fibers (ACFs) were investigated by different heat-treatment temperature of the pitch-based ACFs in order to improve the specific capacitance of electric double-layer capacitor (EDLC). The ACFs were prepared by different heat-treatment temperatures of 1050 and $1450^{\circ}C$, after activation with 4 M KOH at $800^{\circ}C$ using stabilized pitch fiber. The specific surface area of prepared ACFs increased from $828m^2/g$ to $987m^2/g$, also the micropore and mesopore volumes of prepared ACFs were increased. These results because pore was produced by desorbing oxygen and hydrogen elements within the ACFs, and pore size was increased by contraction ACFs by heat-treatment process. Because of the porous properties, the specific capacitance was increased from 73 F/g to 119 F/g using cyclic voltammetry with 1 M $H_2SO_4$ at scan rates of 5 mV/s.